European Crane Fly Control in Lawn - Ask Extension
European Crane Fly Control
I installed new front and backyard grass 18 months ago. This past spring I began to notice areas of dead grass - the ar...
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European Crane Fly Control in Lawn #856664
Asked December 26, 2023, 4:29 PM EST
European Crane Fly Control
I installed new front and backyard grass 18 months ago. This past spring I began to notice areas of dead grass - the area does not appear yellow yet the blades are dull and withered. I browsed the internet and believe I have a Crane Fly issue. A neighbor confirmed his problem a few years ago which led to having the lawn removed.
I then contacted a local lawn pest management business which confirmed my issue. I have even seen Crane Flies in my yard. The business applied a product to control the flies but the problem continued.
I then consulted a website “DoMyOwn” for a plan of action. A consultant recommended Merit 0.5 G Granular Insecticide. This did seem to help over the summer but as fall came there were many more areas of dead grass. I again asked for further assistance as was told my another consultant the following:
“The Talstar PL Granular Insecticide only talks about their larvae not the eggs & Merit only talks about the eggs. I would apply the Merit first to prevent as many eggs from hatching as possible & then follow up with the Talstar to get rid of as many larvae that did hatch. I would advise working with your local extension office, link below, for proper timing of both of these products. While you may not get complete control of them, you will definitely see less of them & less damage.”
Questions:
Are these the best insecticides to use?
Do I have to use both of them to control the flies and larvae?
How often and how much should be applied to my lawn?
Why is my lawn the only one in the nieghborhood as I can see with this issue?
Is there a preventative method to erradicate the flies rather than trying to killl them and/or their larvae with chemicals?
Are the flies attracted to flying insect traps of any kind?
Any suggestions would be greatly appreciated. I feel a few more months of the fly infestation and my lawn will be destroyed.
Thank you for your time,
Tigard, Oregon
<personal data hidden>
Washington County Oregon
Expert Response
First, I refer you to an existing extension publication on Managing Crane flies in Lawns. https://catalog.extension.oregonstate.edu/sites/catalog/files/project/pdf/em9296.pdf
This publication covers pest biology and management strategies, answering the questions you have raised above and listing the insecticides that are effective for European crane fly control for home lawn use and restricted use. It was unclear whether you hired a professional to control or did it yourself. Various insecticide chemistries work differently- some products are ovicidal, and some are larvicidal. No control for adult flies is recommended. Spring application is recommended for targeting larvae using either contact or systemic insecticides, and fall application prior to egg hatch might suppress further damage.
Larvae hatch in late summer (Aug.-Sept.) and feed through winter and into spring, causing the most damage in the spring (April and May). This pest overwinters as a third-instar larva in the soil. Adult emergence may begin anytime from July to mid-October. Adult males are 14 to 19 mm in length, and adult females are 19 to 25 mm long. Adult crane flies do not feed-they only drink water-and their life expectancy is 2 to 14 days. They usually mate and lay eggs within 24 hours of emergence. Eggs are laid in turfgrass. Eggs and early instar larvae require a very moist atmosphere or high mortality will occur; therefore, populations are greatest in turfgrass adjacent to saturated soils. Eggs hatch in approximately 11 to 15 days. The young larvae develop rapidly through to the third instar, known as leatherjackets, in which state they overwinter. At this stage, the larvae feed on the turfgrass through the winter months into the spring, causing the most damage in April and May.
For more details on suggested
insecticides and specific usage rates, refer to the Pacific
Northwest Insect Management Handbook (https://
pnwhandbooks.org/insect) and the insecticide label.
https://pnwhandbooks.org/insect/hort/turfgrass/turfgrass-crane-fly
The key to preventing crane flies is maintaining healthy turfgrass. Follow Practical Lawn Care for Western Oregon, EC 152, https://catalog.extension.oregonstate.edu/ec1521
I hope all of this is helpful.
This publication covers pest biology and management strategies, answering the questions you have raised above and listing the insecticides that are effective for European crane fly control for home lawn use and restricted use. It was unclear whether you hired a professional to control or did it yourself. Various insecticide chemistries work differently- some products are ovicidal, and some are larvicidal. No control for adult flies is recommended. Spring application is recommended for targeting larvae using either contact or systemic insecticides, and fall application prior to egg hatch might suppress further damage.
Larvae hatch in late summer (Aug.-Sept.) and feed through winter and into spring, causing the most damage in the spring (April and May). This pest overwinters as a third-instar larva in the soil. Adult emergence may begin anytime from July to mid-October. Adult males are 14 to 19 mm in length, and adult females are 19 to 25 mm long. Adult crane flies do not feed-they only drink water-and their life expectancy is 2 to 14 days. They usually mate and lay eggs within 24 hours of emergence. Eggs are laid in turfgrass. Eggs and early instar larvae require a very moist atmosphere or high mortality will occur; therefore, populations are greatest in turfgrass adjacent to saturated soils. Eggs hatch in approximately 11 to 15 days. The young larvae develop rapidly through to the third instar, known as leatherjackets, in which state they overwinter. At this stage, the larvae feed on the turfgrass through the winter months into the spring, causing the most damage in April and May.
For more details on suggested
insecticides and specific usage rates, refer to the Pacific
Northwest Insect Management Handbook (https://
pnwhandbooks.org/insect) and the insecticide label.
https://pnwhandbooks.org/insect/hort/turfgrass/turfgrass-crane-fly
The key to preventing crane flies is maintaining healthy turfgrass. Follow Practical Lawn Care for Western Oregon, EC 152, https://catalog.extension.oregonstate.edu/ec1521
I hope all of this is helpful.
Thank you for your time and knowledge to address my problem with Crane Flies. Much appreciated.
Trudy
You are very welcome!
What process might you suggest for regrowing the dead grass areas caused by the Crane Fly larvae?
Thank you,
Trudy
I suggest replanting and reseeding. Once there is this damage to roots, you can do nothing to recover. Also, follow the best management practices guidelines for turfgrass management in the extension article sent earlier.
you are welcome
Ask Extension,
You were so helpful with my Crane Fly questions and I seem to have them somewhat under control - thank you!
Now I have another issue with my backyard grass in certain areas. The blades of grass appear yellow and are not growing like the rest of the lawn. I noticed this last fall but was so concerned with the fly issue that I put off dealing with it. Could you again give me some suggestions to correct this issue?
Attached are pictures of the area.
Trudy
I am sorry. This will need diagnoses by our plant clinic experts. I am unable to diagnose from pictures. https://bpp.oregonstate.edu/how-submit-plant-materials
Please send samples to the OSU plant clinic for further queries. Thanks,
Navneet
Please send samples to the OSU plant clinic for further queries. Thanks,
Navneet
Thank you, I will do that.
you are welcome!